2 Questions to Ask Yourself First

Will you still use a condom to protect against STDs? Male condoms offer the best protection against STDs. With all other methods of contraception, you should also use a condom.

How likely are you to forget pills now and then? The answer matters, because it affects how well the pill works. "You should swallow a pill at the same time every day, whether or not you have sex," the FDA's web site states.

When taken correctly, the pill is highly effective at preventing pregnancy. But that phrase "when taken correctly" is key.

About 8% of women who take the pill become pregnant unintentionally each year. In most of those cases, the women forgot to take pills. Yet when used perfectly -- every day at the same time of day -- only 1 in 100 women have an unintended pregnancy during the first year of using the pill.

So yes, the pill works. But it's not ideal for women wanting a contraception method that they don't need to think about.

"It's a very effective method for women who remember to take their pill each and every day at around the same," says Elizabeth Micks, MD, an instructor and fellow in family planning at Oregon Health and Science University.

Birth control methods that don't require daily action on the woman's part, such as intrauterine devices (IUD) and contraceptive implants, have significantly lower failure rates.

If you've answered those questions and decided that you want birth control pills as your form of contraception, here are the options.

Types of Pills

There are two main types of birth control pills: combination pills and progestin-only pills. Most pills are available in both a 21-day or a 28-day pack. They are often classified on the amount of estrogen and/or the amount and type of progestin.